Incendium
by KeepCalmAndExpectoPatronum
Summary: Severus and Tonks are in a happy and loving relationship. Everything would be perfect were it not for Severus'...affliction. Despite exploring all avenues, he is no closer to solving his magical malady. His last hope however comes in the form of none of than Healer Neville Longbottom. What could possibly go wrong?


_Originally written for the Quills & Parchment One Shot Competition #9: Healer and Mediwizard_

 _Winner - Most Creative Injury/Jinx/Accident_

 _Thank you to my loyal beta, Nymphadorable, for their time and work on this story!_

 _UPDATE: The wonderful Potterotica Podcast read this story out on their show recently. The commentary is hilarious and definitely worth a listen! The episodes are available through P atreon, so if you love live readings of smutty, funny Harry Potter fanfiction, you should definitely check it out!_

* * *

Severus Snape's life had never been easy. He had been beset with troubles from the day he was born: raised in poverty with an abusive father and helpless mother; bullied mercilessly throughout all of his school days; self-inflicted miseries like pushing away the only real friend he ever had through his own cruelty and stupidity; becoming a Death Eater then seeking penance for his actions until finally the Dark Lord fell once and for all; even then, life gave him no respite. He survived the war barely intact, the scars on his neck a constant reminder of how close he came to losing it all. No, Severus Snape's life had been hard, and it had been painful. But never in his life had he felt more humiliated than he did in this moment.

He glanced over at the receptionist's desk and sighed. The sign above the desk read 'Department of Psychomagical Maladies and Injuries', and it made Severus bristle every time he laid eyes upon it. He shouldn't be here.

A warm hand rested over his clenched fist, "You alright, Sev?"

Severus glanced at Tonks. Her eyes, today shining in varying shades of black and grey, looked at him wide with worry. He unclenched his fist and took her hand in his own, "I don't want to be here."

"I know," she said sympathetically. "But you said it yourself, we can't continue like this. Just…try. For me."

He bowed his head and nodded, "Count your blessings that I love you more than I hate everyone else."

Tonks smiled and placed a chaste kiss on the back of his hand, "I love you, too. Even if you are the grumpiest person I know."

"I am not grumpy," he grumbled. "It is everyone else that is the problem. I simply have a low tolerance for stupidity, and unfortunately the majority of people are intolerably stupid."

Tonks sniggered and shook her head, "Just because most people are less intelligent than you doesn't make them stupid. I'm not as smart as you, does that make me intolerably stupid?"

"No," he smirked. "You are more tolerable than most."

Tonks laughed and punched him in the arm, "Cheeky! Or was that supposed to be a compliment?"

"I don't do compliments," he drawled.

Tonks rolled her eyes and whispered to him, "Not in public, anyway."

"Compliments and praise are insincere," he argued. "I only tell you what is factual."

Tonks grinned mischievously, "So when you tell me that I'm beautiful, you're simply relaying the facts?"

"Exactly," he inclined his head towards her and she rested her forehead against his, squeezing his hand tightly.

No, Severus Snape's life had never been easy or straight-forward, but against all odds and reason, he had been granted a second chance at life in the form of Nymphadora Tonks. He would never understand what she saw in him – he knew his mannerisms were abrasive at the best of times, he wasn't romantic or charming or anything like what in his mind this woman deserved. But she had persisted in her pursuit of him, saying that she liked that he didn't bullshit her like everyone else did. He couldn't deny that – he would always be honest with her, although he had to accept sometimes that there was a difference between being honest and being right. Despite his own reciprocal feelings, he had resisted starting a relationship with her. He feared the weakness that love made of men in the face of adversity, and as a double agent he couldn't give Voldemort any inkling of his true allegiance. Besides, he had no expectation that he would ever survive the war. But when he had woken up in St Mungo's weeks after the Final Battle, she had been by his bedside. She proved him wrong, that love was no weakness – it gave him the strength to fight back, and with her help build a new life for himself, one free from war and pain. Three years had passed, and she hadn't left his side since.

Three years of happiness, but still he couldn't give her what she really wanted – what he really wanted too. A full and loving relationship from both parties was impossible given his…affliction. Hence why he sat here now, willing to humiliate himself for the woman he loved, to give her everything she wanted in life. It was the least he could do to repay her for giving life back to him, one that was finally worth living.

* * *

Neville stared at the name written in his diary of his next patient with mounting unease. Severus Snape, his old potions professor, the bane of his existence at Hogwarts - his boggart for Merlin's sake. He rubbed his face nervously. This was not going to go well.

Neville scolded himself – he wasn't a school boy anymore, he was a grown man. A medical professional, the best in his field. Severus Snape was simply another patient. He told himself he was worrying over nothing – both men would act calmly and professionally.

He pressed the buzzer to call his receptionist, "Euan, can you send through Mr. Snape, please?"

"Yes, Healer Longbottom," rang Euan's voice cheerfully. Neville took a deep breath to calm his nerves.

 _You can handle this Neville_ , he told himself. _Just be calm and confident_.

There was a sharp knock at the door.

"Come in," he squeaked.

The door flew open and Severus Snape stepped into the office. His black eyes fell on Neville and he paused, an unreadable expression on his face. Then he turned and left, slamming the door shut behind him with such force that Neville jumped.

And with that the session was over.

Two seconds. It had to be a record.

* * *

Severus swept past Tonks towards the elevator.

"Woah," she grabbed his arm and turned him to face her. "Where do you think you're going?"

"Did you know?" he hissed. "That it was _him_ we would be seeing?"

Tonks bit her lip. Severus snarled and turned on his heel, Tonks chasing after him, "I knew you wouldn't go if you knew it was Neville."

"Yet you went ahead and booked an appointment anyway," he spat pressing the elevator button aggressively several times. "Did you think that by tricking me into his office that I would take no notice of what bumbling buffoon would be sat behind the desk?"

"He's not a buffoon!" she scolded. "He's the best psychomagical practitioner in the country. I arranged the appointment with him because he's the best!"

Snape tapped his foot impatiently waiting for the elevator to arrive, "Somehow I find that very hard to believe. The boy could hardly hold a quill without causing mayhem in my classroom."

"If that really is true then I'm going to hazard a guess that was probably a lot to do with you," she drew him an accusatory look.

Severus snorted, "Even so, I cannot believe that he was the best to choose from."

"His credentials are sound," she argued. "Remus and Sirius were treated by him a few months ago, they said he did wonders for them."

Severus rounded on her, "Lupin and Black know that I'm here?"

"Of course not!" she replied irritably. "I told them I was making the appointment for myself and they were courteous enough not to ask questions. Besides, I know Sirius well enough if I had told him it was for you, he would probably have sent you to some quack healer as a lame attempt at humour, so please give me a little more credit!"

The elevator pinged and the door slid open. Severus went to step inside but Tonks pulled him towards her. He tried to shake her free but she held her grip.

"Let go of me, you incessant woman!" he snarled.

"No!" she snapped pulling him away from the elevator. She may have been slight in size but she was surprisingly strong. They stood their struggling with each other for a moment while the receptionist looked on with bemusement but chose not to intervene – it wasn't even the strangest thing he'd seen that day. The elevator door slid shut and the lift began to descend.

Tonks loosened her grip and Severus glared at her.

"I'll take the stairs, then," he mumbled heading for the stairwell.

Tonks hurried after him, "Sev, will you just listen to me!"

"There is nothing more to discuss," he growled striding down the first few steps. "I will not subject myself to further humiliation by divulging my medical maladies to the likes of Neville Longbottom!"

"So you'd rather suffer in silence?" she sneered.

"Yes!" he snapped.

Tonks stopped chasing after him then and sank defeated onto a step. Severus paused and looked up at her and felt his heart sink. There she sat, her eyes brimming with tears and her hair as black as his own. She looked desperate.

"You promised!" she cried, her voice becoming strained. "You promised me that you would try."

"I have tried," he argued, his voice softer than before. "I am just as desperate as you are to fix this - I've allowed myself to be poked and prodded by every Healer in this hospital and they still can't figure out what is wrong, and still I tried. But you cannot expect me to go in there and pour my heart out to that boy. It's a humiliation that I don't even think I can bear."

"He's not a boy anymore Severus, he's a Healer," she corrected him. "He's good at what he does, so why won't you just give him a chance?"

Severus folded his arms and scowled but said nothing. Tonks pressed on, "You've said it yourself – we've tried everything. This is our last chance, Severus. Please don't just walk away now without exhausting every possible option."

Severus groaned and pinched the bridge of his nose, trying and failing to keep his feelings of anger, fear and inadequacy churning inside of him in check.

"I hate this," he snarled.

"I know," she sighed rubbing her tired eyes. "I do too. So will you try? Please?"

Severus' shoulders sagged and he nodded. Pulling Tonks to her feet he followed her back upstairs grudgingly but willingly towards ultimate humiliation.

* * *

Neville jumped as he heard another loud rap at the door. He frowned, it couldn't possibly be his next patient; they weren't due to arrive for another hour. He approached the door and opened it wide. Surely it couldn't be…

Severus Snape stood at the door with Tonks holding his arm tightly. Although Neville was the same height as Severus, his old potions master still managed to stare down his nose at him with a look of utmost contempt.

"Longbottom," he greeted him stiffly.

"Professor," Neville held out his hand. "It's good to see you again, sir."

Severus swept passed him without taking his hand and took one of the seats in front of Neville's desk. Tonks grabbed Neville's hand and shook it heartily, "Thanks for seeing us Neville, really appreciate it."

"Not at all," he smiled weakly, mentally counting how many seconds it would take for the man to storm out of the office this time. He closed the office door behind him and sat behind his desk again, "I understand that this is difficult for you sir, but I endeavour to make this as comfortable and as painless as possible for you."

Severus gave him a withering look but said nothing. Neville cleared his throat and flicked through Severus' file, "So can you tell me a little bit about why you're here today?"

"Shouldn't you already know?" he drawled.

"Uh yes, but I prefer to hear it from the patient's point of view," Neville explained.

Severus' lips curled, "I am not inclined to repeat myself, Longbottom. If you are too stupid to read the file I do not see why I should—"

Tonks kicked his leg and he grunted in pain. He glowered at her and shut his mouth. Neville sighed and made a small note, _May not be easily amenable to treatment_ , before adding, _Still an insufferable git_.

He considered his old potions master in silence for a few moments, careful to maintain eye-contact with him. He felt like he was trying to greet a particularly aggressive hippogriff. _An apt comparison_ , thought Neville - both were immensely proud and extremely dangerous.

"Severus—"

"Professor," Severus corrected him.

"Professor," Neville continued. "Can you please give me a summary of your treatment? In case my notes are missing out anything important."

Severus glanced at Tonks who gave him an expectant look. He sighed and spoke carefully, "The other Healers have tried everything – they have checked me for every curse and jinx we can think of. I have tried salves and potions, rituals and incantations – nothing has worked. I have exhausted every means at my disposal. Despite all of this, the Healers remain at a loss as to the root cause of my…affliction. So you Longbottom, are apparently my last hope. Should I stop wasting both of our time and go home now?"

Neville ignored the jibe and took a few moments to scribble down some notes. The silence dragged out as he flicked through Severus' medical file, a deep frown set as he read.

"How long have you been in a relationship together?" he asked still taking notes.

"Three years," said Tonks giving Severus' hand a slight squeeze.

"Your medical files say that your symptoms only present when you are in a state of arousal, is that correct?" he asked flatly.

Severus' eyes narrowed and he replied, "That is correct."

Neville nodded, "And when did the symptoms first present themselves? How far into the relationship?"

Severus shifted uncomfortably in his seat before admitting, "It began almost immediately after we became…"

"Intimate," finished Tonks patting Severus' hand reassuringly.

Neville frowned, "You've been suffering from these symptoms for three years. Why haven't you consulted medical treatment long before now?"

Severus' face twisted into an ugly sneer and he lowered his gaze, "I was...embarrassed about my predicament. I thought that if I ignored it, the problem would eventually resolve itself."

"But it hasn't," said Neville.

Severus sneered, "It would seem not, wouldn't it?"

"It's gotten worse over time?" he asked.

Severus nodded, glaring at his feet.

Neville scribbled another note, "So you aren't sexually active at all at the moment?"

Severus' head snapped up to face Neville and he snarled, "That is none of your business!"

"Sev," chided Tonks gently then added. "We have an active albeit one-sided sex life – Sev can pleasure me, but I can't give anything in return."

"Because of the spontaneous combustion," Neville finished.

"Correct," Severus confirmed quietly.

Neville nodded and scribbled in his notebook again, "When you are intimate, how do you prevent yourself from becoming aroused?"

Severus clenched his fists in his lap and said flatly, "I take potions to stop myself."

"I see," said Neville. "So to be clear, even just being in a state of sexual arousal literally causes you to burst into flames?"

"Yes," he snarled through clenched teeth.

"Does the fire increase in severity when you achieve orgasm?" asked Neville.

Severus drew his wand then and Neville flinched, but Tonks pushed Severus' wand arm down.

"Severus!" she scolded. "Sit down and behave yourself, for Merlin's sake!"

"He has no right asking questions like that!" he shouted pointing at Neville accusingly.

"I need to ask these questions to get a clearer picture of the problem," Neville explained. "I'm sorry it's embarrassing sir, I'll get through the questions as quickly as possible. Shall I continue?"

Severus gritted his teeth and spat, "Fine! Get on with it!"

"Would it be easier to answer these questions if we were on our own?" he asked cautiously glancing at Tonks.

Tonks looked at Severus, "If it's easier I'll leave."

Severus hesitated, "Perhaps. If you don't mind…"

"Not at all," she reassured him rising to her feet. "I'll be waiting outside if you need me."

"Thank you," said Neville, waiting til she had left the room to continue his questions. "I'm curious – why are you only seeking treatment now?"

Severus hesitated before answering, "We have decided that we want to have children. But my current condition obviously makes that impossible."

Neville nodded in understanding. He cleared his throat and avoided Severus' gaze when he asked the next question, "Would you describe yourself as…sexually inexperienced?"

"Excuse me?" he hissed, looked positively incensed.

"Would you describe yourself as sexually inexperienced?" Neville repeated calmly. "Are you a virgin?"

It was taking every fibre of Severus' being to stop himself sending a barrage of curses straight into Longbottom's stupid face. He took a deep breath and answered, his voice barely above a whisper, "And what if I am?"

Neville smiled, "Then I think your problem is much easier to solve than we originally anticipated."

Severus blinked. He couldn't possibly have heard Longbottom correctly.

"If it is so easy to solve, then why haven't any of the other Healers been able to fix it?" he snapped.

"Because your problem isn't magical – not entirely," he explained. "I believe you are suffering from acute sexual anxiety."

"I am suffering a great deal of anxiety right now, but that is entirely your doing, Longbottom!" he shouted, struggling to keep the feelings of anger and embarrassment from overwhelming him.

Neville ignored the outburst and continued, "Anxiety can be defined as a feeling of apprehension and fear characterised by physical, psychological and in your case, magical symptoms - I believe that given your history, it is not all that surprising. Although fire is unusual it is not an unheard of side-effect."

Severus' eyes widened in surprise, "So…this has happened to other people?"

"It has," Neville confirmed.

Severus licked his lips and asked slowly, "And it is treatable?"

Neville smiled, "It is."

Some of the tension in Severus' shoulders seemed to ease then. So there was a cure after all, and Longbottom of all people knew what it was. He frowned at Neville and asked, "Do you know what would have caused my affliction in the first place? Is it merely…sexual inexperience?"

Neville shook his head, "No, I believe that you are the victim of your own success, so to speak."

Severus' eyes narrowed, "What do you mean?"

Neville shrugged, "You've kept your true emotions under lock and key for most of your life – working as a double agent during the war, not allowing yourself to feel the same emotions as everyone else—"

"I couldn't though, could I?" spat Severus. "If the Dark Lord knew my true feelings then he would have killed me!"

"Of course," Neville agreed nodding sympathetically. "But years of suppression has caused your body to manifest these latent emotions in the form of fire - that is why your symptoms only began to present when you began a relationship with Ms. Tonks."

"So how do you suggest I get these emotions under control?" asked Severus.

"I believe the best course of action is to confront the problem head on. Since you spontaneously combust when you are aroused-" Severus sneered when Neville said aroused. "You are going to have to um, follow through with your activity so to speak. And keep doing so until you learn to get your emotions and your magic back under control."

Severus said nothing for a few moments. To his annoyance, he could see no fault in Longbottom's reasoning. He gave a slow nod, "That sounds…acceptable."

Neville smiled, "Excellent. We have specialised facilities in place here at St Mungo's for you to complete your treatment—"

"You expect me to do it here?" Severus asked incredulously.

"Well, we can't allow you to do it at home, can we?" asked Neville raising an eyebrow. "You could burn your whole house down."

Severus scowled but relented, "Very well. When am I to begin treatment?"

Neville consulted his diary, "We can begin treatment tomorrow. I'll book out the specialist room for you for the entire weekend just to be safe."

"The whole weekend?" snapped Severus. "How long do you expect this to take?"

"It all depends on you, Professor," shrugged Neville. "Resistance will only prolong your treatment."

Severus snarled. He had never submitted to anything readily in his entire life, now Longbottom expected him to abandon a lifelong habit and do it now. His mind wandered to Tonks, still sitting waiting outside, sure that he was fulfilling his end of the bargain and trying his best – for her. He sighed in grim resignation – a promise is a promise.

"Very well," he grumbled.

Neville nodded and made a note in the diary before snapping it shut, "Shall we call through Tonks and tell her we've come to a decision on your treatment?"

"That is Ms. Tonks to you boy, mind your manners!" he snapped.

"Sorry, sorry," muttered Neville apologetically heading for the door. He popped his head out of the office and called, "Ms. Tonks, would you like to come through now?"

"That's better," grumbled Severus.

Neville held the door open for Tonks and closed it behind her before taking his seat behind his desk again. Tonks sat down next to Severus and immediately took his hand in her own. She looked between the two men expectantly, "So what's the prognosis? Can you help?"

"I believe I can," said Neville. "Severus' affliction appears to be psychomagical in nature. We've both come to an agreement that the only course of treatment is to face the problem head on. We have ascertained that Severus loses control of his magic and spontaneously combusts whenever he becomes aroused—" Severus bristled again at the word. "So the only way that he is going to be able to control his magic is with…practice. We have booked him into one of our specialist treatment rooms for the weekend. It's very comfortable, you'll have everything you need provided for, and the room is of course fireproof."

"How fireproof?" she asked curiously.

"Enough to contain Fiendfyre," he assured her.

Tonks nodded, "Am I able to stay with him during his treatment?"

Severus looked at her sharply, "Absolutely not. It's too dangerous."

"I'm not letting you go through this alone if I don't have to," she said fiercely. She looked at Neville, "Is it possible then? For me to be there?"

Neville thought for a moment then nodded, "Yes, if you take an Ice Potion at regular intervals then I don't see why not. If anything it may be beneficial to his treatment."

Severus looked incensed, "I will not have you put yourself in danger on my account."

"I won't be in danger if I take the Ice Potion," she reassured him. "There are two people in this relationship Severus. I promised you when we came here that I would be with you every step of the way, and I meant it. If my being there helps, then it would be stupid not to have me there."

"But what if I hurt you?" he asked weakly.

Tonks squeezed his hand reassuringly, "You won't. I trust you, Sev. Trust me now. Please."

Severus ran a hand through his hair and grimaced. What was it about this woman that meant he could never say no to her?

"Fine," he snapped. "But I'm making the potion myself. I don't trust your staff here to make one up to a sufficient standard."

He glared at Neville as though daring him to challenge him, but Neville nodded in agreement, "That's perfectly fine by me. Come back here tomorrow at six o' clock to begin your treatment. Bring a bag with everything you'll need over the weekend."

* * *

The next evening Severus and Tonks returned to the hospital, both looking apprehensive. Neville tried to reassure them, "Everything will be perfectly safe. I'll be on the premises the whole time in case you need me. You brought the potions?"

Tonks pulled a small glass vial filled with black liquid out of her pocket and showed it to Neville. He nodded, "Follow me, please."

He led them down a long corridor and stopped in front of a plain white door. He motioned to Severus to come forward, "This room is similar to the Room of Requirement at Hogwarts – it will provide everything that you need, but you need to be the one who opens the door."

Severus pushed the door open and ushered Tonks inside. Neville stepped forward and said, "I'll be in the room across the hall. If you need anything don't be afraid to—"

Severus slammed the door shut in Neville's face and turned to observe his strange, new surroundings. Although the room was odd in appearance, it was cosy and welcoming; the rough stone walls were draped in black organza, and the honey-coloured wooden floor was covered in a carpet so thick it muffled their footsteps as they stepped further into the room. Severus eyed the room curiously, "The room looks a little bit like the Slytherin dungeon."

"You know now that you mention it," said Tonks slowly. "It reminds me of the Hufflepuff Common Room."

"Strange," he mused looking overhead and his eyes widened as he saw not a ceiling, but an open sky adorned with beautiful, slow-moving solar systems and the occasional shooting star. Tonks looked up and she gasped.

"Wow," she breathed and took Severus' hand in her own. Severus lowered his gaze and his eyes fell onto the large four-poster bed at the centre of the room and felt a rush of mild panic and arousal arise in him. Already he could feel a hot coil twisting in his stomach, threatening to rise. Tonks pulled him towards the bed and flopped down onto it grinning broadly, "Black silk sheets, Severus? This was definitely your contribution."

Severus huffed, "They won't last long now that I'm here."

Tonks rolled onto her side and propped herself up on her elbow to study Severus, "I'm not here for the fancy bedsheets, Sev. I'm here for you." She pulled the vial filled with the ice potion from her pocket, uncorked it and toasted, "Bottom's up," before downing the contents in one large gulp. She closed her eyes and waited, but nothing happened.

"How do I know if it's working?" she asked peeking out of one eye.

Severus cocked an eyebrow, "Don't you trust my potion-making ability?"

"'Course I do!" she smirked. "I plan on putting your concoction through its paces this weekend."

A smirk tugged at the corner of his lips, "I suppose there's only one way to find out if the potion is working."

Grinning more broadly, Tonks knelt on the bed and pulled Severus towards her, snaking her hand around his waist and holding him firmly in place. He looked into her eyes, wide with expectation and longing. He licked his lips, his mouth suddenly felt very dry, and pressed their lips together in a chaste kiss. Tonks sighed and opened her mouth a little in invitation, and Severus traced his tongue along her bottom lip before deepening the kiss, brushing his tongue against her own. Severus slowly ran his hands down the small of her back over the swell of her small, perk arse, giving it a light squeeze. Tonks responded by thrusting her hips forward and smiled as she felt Severus' growing erection press into her.

Already there was steam coming off of Severus' shoulders, his skin shining with sweat.

"Let's get rid of these clothes, shall we?" she whispered. Usually at this point Severus would be too hot to even have physical contact with, but his skin felt cool to her touch – the potion must be working.

Tonks' hands were slight and nimble, making fast work of unfastening the many buttons on Severus' coat. She slipped her hand through his robes, brushing her fingers across the taut, smooth skin of his abdomen before peeling it back to expose his pale, lithe shoulders. The material slid off of his back and fell in a heap on the floor, and soon Tonks' hands and lips were everywhere, placing open-mouthed kisses and gentle bites down Severus' neck towards his nipples, palming his growing erection through his cotton trousers.

Severus felt light-headed. Tonks' intoxicating scent was all around him – something sweet and floral that was so distinct to her. He buried his head into her neck and kissed her again, she tasted as good as she smelled, it was making his head swim. He slipped his hand beneath the front of her jeans and Tonks gasped as Severus' fingers came into contact with her wet folds, and she pressed her hips forward into his touch.

They both trembled with nervousness and arousal. He had waited so long, wanted this for so long, he was afraid that his desire would burn through him and consume him entirely. Severus suddenly gasped as violet flames began to lick his skin, up his arms and along his abdomen and chest. He instinctively took a step back breaking contact with Tonks, afraid.

"It's alright," she reassured him reaching for him. "Come closer."

"I don't want to hurt you," he warned shaking his head.

Tonks paused then nodded.

"Okay, let's take this slow," she said quietly. "For now, just watch."

Tonks knelt back on the hinds of her legs and peeled off her top to reveal her soft, supple breasts, her pink nipples already stiff. Severus sighed and drank in the sight of her – the smattering of freckles on her nose and bare shoulders, the curve of her feminine hips - everything about her was soft and feminine and delectable. The fire on Severus' skin grew in intensity with the growing feeling of want and arousal inside of him. Tonks gave him a wry smile and quickly peeled off the rest of her clothes, lying naked on the bed for Severus to peruse over.

Severus cast his eyes over her and his breath hitched at the wondrous sight before him – Tonks' eyes, half-lidded and dark with arousal, watched him intently. She slowly traced a hand down passed her chest which was rising and falling rapidly, brushing a finger against one of her nipples and a small gasp of pleasure passed her lips. Lower still her hand traced along the soft, smooth skin of her abdomen, across curve of her hip and between her thighs, teasing her clit with the tip of her index finger. She let out a shuddering breath and her hips raised in invitation to him.

Severus groaned and palmed his erection through his trousers, trying with difficulty not to come at the mere sight of Tonks pleasuring herself. Tonks licked her lips and when she spoke her voice was low and husky, "I want to watch you touching yourself, Sev."

Severus let out a shaky breath and obeyed, quickly freeing his aching erection from the constraints of his tight trousers. He leaned against the frame of the four-poster bed to steady his shaking legs and gripped the base of his cock, slowly sliding his hand up and down his hot shaft.

They watched each other intently for a while, Severus desperately aroused but afraid to touch her, although he could feel his resolve quickly melting away. When Tonks' breathing became more laboured, her chest rising and falling quickly and her eyelids began to flutter, he knew she must be close. Throwing caution to the wind he climbed onto the bed and reached out, ever so gently brushing his fingertips across her calf. Tonks' eyes widened and she let out a sharp breath of relief as the fire danced harmlessly across her skin. It didn't hurt, if anything it felt pleasant to the touch like warm kisses across her flesh. She looked hungrily into Severus' eyes and let her legs open wide for him, tilting her hips invitingly and Severus felt a rush of answering heat spread in his groin and down his legs, burning his trousers to ash to reveal a naked body aflame.

He slowly ran his hands up her inner thighs towards the soft bed of curls between Tonks' legs, gently grazing her clit with the tip of his tongue. Tonks let out a shuddering gasp and rolled her hips, encouraging Severus' tongue to press closer to her body. Severus, now sure that he wouldn't hurt her, sighed contentedly as he leaned closer, gently sucking and teasing her clit with his tongue and lips. Tonks' thighs began to quiver and she was panting more loudly.

"Sev," she whimpered. "I'm close."

Severus groaned and began to lap at her clit with more fervour, slipping a finger in and out of her to the same rhythm of his tongue. Tonks ran her fingers gently and lovingly through Severus' silken hair, then grabbed it tightly in her fist as her climax approached. Her whole body stiffened and she involuntarily thrusted her hips upward into Severus' face. He groaned happily as he felt her body spasm and shake, her velvety walls contracting against his fingers as he continued to finger her over the crest of her orgasm. He only stopped when he felt her relax and begin to shiver.

He rested his cheek on her inner thigh and she traced the outline of his jawline with her fingertips. Her hair was like a rainbow now, a beautiful array of ever-changing colours.

"That was amazing," she breathed. She reached for his hand and gave him a mischievous grin, "Your turn."

More confident and relaxed now, Severus grinned broadly and crawled towards her, resting the weight of his body on top of her as she wrapped her legs around him and pulled him into a deep, languid kiss. She pulled away and looked up at him, the heat returning anew to her eyes. Rising up, Severus positioned himself over her entrance and slowly sank into her and he gasped at the intensity of the feeling, his whole body ablaze now. Christ, he had wanted her for so long and now that he had her, he wanted to give everything of himself over to her.

Severus kissed her again and began to move, tentatively at first and then finding a rhythm, relishing the feel her soft, warm body against his own. He kept moving like that, thrusting in a slow, steady rhythm that continuously brushed against her swollen clit. Little shivers of pleasure ran down the full length of his back as moans of pleasure escaped Tonks' lips, her hot breath pressed against his neck. His hands braced on either side of her, fingers grasping the sheets beneath him which began to smoke and sizzle under his fingers, but he no longer worried nor cared. He was too lost in the feeling of her underneath him and all around him, the heat of her silken walls pressed against his aching length as he rocked his hips back and forth, her arms and legs wrapped tightly around him pulling him closer, kissing him hard as his thrusting increased in speed and strength.

Their bodies pressed flush against each other but Severus tried to clutch her closer still. He needed more of her, all of her, he wanted to be consumed entirely by the feel of her against his skin, the sound of her ragged breaths and sweet moans filling him up until they overflowed and poured out of him. His eyes burned into Tonks. No, his eyes were literally burning orbs of orange fire, there was something frighteningly beautiful at the sight of Severus relinquishing all control to pleasure, to her. His panting became increasingly ragged, a sharp flowering bloomed in the pit of his stomach and rose through him fiercely, causing his back to arch and the fire and light of his orgasm to set him alight entirely.

He cried out as he came and it was like an atom bomb exploding into life, a magical, sexual fission causing him to transform entirely, no longer flesh and bone, only light and fire and heat and all-consuming pleasure.

Fire was everywhere. Crawling up the walls, burning everything in its path, swallowing up the organza hangings and furniture and the plush rug on the floor. All turned to ash and still the fire burned, occupying every space of the room, reaching up towards to endless swirl of galaxies lurching overhead. But Severus and Tonks paid it no mind, too lost in the pleasure of their own fire, willingly devoured by it.

* * *

Three days had passed and still Professor Snape and Tonks hadn't emerged from their room. Neville was beginning to worry. He had felt his walls shudder a few times the first day with the sheer force of the fire that Severus' body was emitting, but Neville wasn't worried - it was to be expected, even. The second day it only happened a couple of times, then nothing. Neville had assumed then that his treatment must be working. He was keen to check up on their progress, but he didn't want to interrupt proceedings either.

One the third day however he couldn't wait any longer. He knocked politely but firmly on the door and called out, "Professor Snape? It's Neville, I'm just checking up on you and Ms. Tonks. It's uh, been three days now and we haven't seen hide nor hair from either of you," he gave a weak laugh then added more seriously. "I just want to make sure that you're both okay."

Neville waited.

"Professor Snape?" he called out again uncertainly. A moment later the door flew open and Neville took a step back and gasped as heat and smoke came pouring out of the room. After a moment Snape's face appeared through the smoke, sweaty and to Neville's mingled sense of professional pleasure and personal discontentment, smiling.

"Neville!" Snape greeted him. "Sorry, we seem to have lost track of time in here. How can we help you?"

Neville stared, "Uh…just checking up on you both. How are things progressing?"

Snape shrugged and said, "Getting better the more we work at it, I only burst into flames when I achieve orgasm now, so it's a vast improvement!"

"Excellent!" nodded Neville approvingly.

"Who is it?" called Tonks from inside the room.

"It's Neville!" shouted Snape over his shoulder.

"Hi Neville!" she called.

"H-hello there," called Neville eyeing Snape uncertainly. He seemed so much more relaxed and (dare he say it) friendlier than usual.

Snape turned back to Neville and said more seriously, "I think we're going to need another couple of days in here to iron out the kinks. You understand, yes?"

Snape was already closing the door on Neville's face. Neville nodded, "Yes! Of course! Take your time."

The door slammed shut and Neville grinned, satisfied that another patient would be leaving the clinic cured. Well, in two days at least…maybe three.


End file.
